The Transdimensional Energy Descent Cosmological Program: A Unified Cosmological Framework Based on Dimensional Interface Dynamics

Current mainstream cosmology and particle physics adopt a domain-separated effective-theory framework. The ΛCDM model successfully describes large-scalecosmic evolution, yet the physical nature of dark matter and dark energy remains unresolved, and the underlying mechanism for singularities and early inflation ismissing. The Standard Model of particle physics unifies three microscopic interac-tions but cannot incorporate gravity, while the ontological dynamical mechanism formass–energy conversion has long been left open. General relativity and quantum mechanics exhibit irreconcilable conflicts at the Planck scale. Leading quantum-gravity proposals introduce many independent ad-hoc assumptions and have long lacked exclusive observational predictions that can be directly tested. This paper presents a unified cosmological research programme built upon high-dimensional energy cascading across dimensional boundaries and dimensional inter-face tension. The programme starts from four foundational axioms and defines the speed of light c as the intrinsic interface velocity at which high-dimensional energycascades into three-dimensional space. Within this framework, mass is not an intrin-sic static property of particles; instead, it emerges as a steady-state manifestationafter cascading energy is retarded by crowding collisions and interactions within the 3D space, providing a continuous dynamical interpretation for the mass–energy relation E = mc2. In this framework, the Big Bang singularity corresponds to a white-hole channel injecting energy from four dimensions into three dimensions. In the early universe, energy density within an extremely small volume exceeded the saturation thresh-old of the 3D host medium. Energy units crowded and collided intensely, causing rapid decay of the cascade velocity and bulk generation of matter within an ex-tremely short timescale, corresponding to cosmic inflation. Free cascading energy that avoids collisional retardation propagates at near-light speed and forms the cos-mic microwave background radiation. Gravitation, electromagnetism, and nuclear forces are interpreted as derivative effects of transdimensional interfacial tension emerging across different scales and dimensional combinations. The apparent ran-domness of quantum states arises from temporal aliasing caused by the limited observation bandwidth of 3D measurement; quantum entanglement corresponds to multiple 3D projections of a single high-dimensional object, naturally evading local hidden-variable and superluminal causal paradoxes. This work presents a set of testable observational predictions together with a full suite of first-order phenomenological dynamical equations, guiding future quan-titative validation and discriminative experiments. This programme is an ontolog-ical unified framework and does not negate the computational validity of existingphysical theories within their respective domains. It aims to connect microscopic, macroscopic and cosmological scales with fewer independent ad-hoc postulates. This version is an open discussion draft (v0.1 revised). Some equations are phe-nomenological placeholders; their parameters and asymptotic behaviours will berefined in subsequent revisions. Revisions and discussion materials are hosted in an open-source repository: https://github.com/nell332/transdimensional-cosmology-program.git, with version records archived on Zenodo: https://doi.org/10.5281/zenodo.23765255.